I have loaded quite a few subsonic loads in 30-30.
Pb 150’s 308241 with @ 4 grains bulleye is nice
A 170 fp bore rider works for me if it’s rubbing it’s nose on the bore.
308403 pope bullet works well too.
I aim for about 960 fps.
I have found that bullet hardness of 50/50 ww/Pb or softer works for me
Soft lube of 60/40 (according to season) be/vas well filled dipped lubed.
Well formed and annealed cases for bullet seating trimmed to max length.partially necksized only.
If just breach seating as is.
I use bulleye a lot and the right amount of airy Dacron filler with the bullet seated firmly into the lands.
This and good follow through as barrel time is long.
The Dacron takes out a lot of vertical dispersion.
I am no benchrester and neither is my rifle and with a 1" dot on my 4x scope I can regularly keep them a tad over an inch at 100 yards and at 300mtre and a keep them in a hand spand.
Not anything up to others levels but I will try them at 200 some time just for fun.
I do like dropping the pope boolet down the barrel and seating it with a pencil or what ever I can find and chambering a case behind it.
Shoot a decent group or object on the range.
The neighbouring shooter with they new looking jacketed rifle in loudenboomer sometimes gets a

look when walking past my target group shot off the bench with no fancy rest and even tries to shoot off hand as well sometimes if I’m practicing shooting a 3" dinger.
Don’t know too much and I won’t win matches but it is sure fun for me.
Ha
FYI my 310 cadet with a heeled bullet with a light charge will cut a 1/2" group at 50 yards.
On a good day when I can see front post and target somewhat clearly though peepsights.
And it’s not the rifle usually that lets me down.